PO-06-148 FIELDBENDING: A NOVEL BIPOLAR PULSED FIELD ELECTRODE CONFIGURATION TO IMPROVE TOLERABILITY

Roya Kamali; Jacob S. Koruth; Iwanari Kawamura; Eduardo Jimenez; Quyen Nguyen; Bart Schade; Shakeeb Bin Hasan; Steven R. Mickelsen

doi:10.1016/j.hrthm.2024.03.1591

Background Tolerability of PFA remains a fundamental challenge as far-field stimulation of excitable tissue can cause discomfort and/or involuntary movement interfering with workflow efficiency. The FieldBending (FB) design by Field Medical Inc. (Cardiff, CA) features an electrode in the catheter's saline irrigation lumen, a non-conductive distal tip, and an external electrode. Current flows from the 3mm external ring, located 4mm proximal to the distal tip, to the internal electrode. Objective This study assesses the FB design in a single-point ablation catheter. Methods COMOL modeling was performed to estimate FB vs Unipolar (UP) field strength at a distance. In 14-day swine models (n=5), the FB catheter was advanced to the atrial septum. Musculoskeletal stimulation was measured using an accelerometer affixed to the sternum. Monophasic 200ns pulse trains (single pulse up to 40 pulses delivered in <100ms synchronized with cardiac cycle) were delivered to catheter tip alternating between FB and UP configurations as a control. The catheter was then used to perform linear point-by-point ablation between IVC and SVC and CTI to evaluate treatment efficacy confirmed with electroanatomic mapping (CardioNXT). Results Simulation predicted 6-fold reduction in distance to reach 1V/cm with FB vs UP (38.2mm vs. 234mm), predicting less far-field stimulation.The novel electrode FB configuration significantly decreased acceleration induced by far-field stimuli, averaging 0.34±0.20 g compared to 3.31±1.14 g (P value < E-10). Electroanatomic mapping demonstrated that FB produced fictional lines of block both acutely and chronically. Gross inspection with TTC staining showed well-demarcated lesions along caval and CTI targets. Histologic findings were consistent with PFA showing homogeneous replacement of myocytes with fibrosis and preservation of integral tissues such as blood vessels, fat, endothelium. Conclusion FB results in a 10-fold reduction in stimulus compared to conventional UP treatment, substantially less than predicted. The FB design can produce effective, contiguous, transmural ablation lines in the atrial swine model. Further, evaluation of the FB design is warranted to better characterize dose optimization and safety.

PO-06-148 FIELDBENDING: A NOVEL BIPOLAR PULSED FIELD ELECTRODE CONFIGURATION TO IMPROVE TOLERABILITY

View Online

Abstract

Details

Metrics